hi everyone, I'm beside myself with worry and hope that someone can help. I had my 20 week scan yesterday and everything appeared normal. They checked the baby's brain and they said the Cisterna Magna was measuring as normal (7mm) apparently it has to be under 10mm but they said it extended slightly and I have to go back for another scan next week. Does anyone know what this means and what the cisterna magna is and does? Many thanks!